A variety of vessels, devices, components and unit operations for manipulating fluids and/or for carrying out chemical, biochemical and/or biological processes are available. For instance, biological materials (e.g., animal and plant cells) including, for example, mammalian, plant or insect cells and microbial cultures can be processed using bioreactors. Traditional bioreactors, which are typically designed as stationary reusable tanks or containers, or disposable bioreactors, many of which utilize plastic sterile bags, may be used for such purposes. Although chemical manufacturing systems, pharmaceutical manufacturing systems, bioreactor systems and other fluid manipulating systems (e.g., mixing systems) are known, improvements to such systems would be beneficial. In particular, systems which include environmental containment that can maintain a sterile, aseptic, substantially particle-free, or reduced-particle environment around or in the system would be useful in a variety of fields, especially for applications involving cell culture, clean manufacturing processes, and use of dangerous materials and/or infectious agents.